Measurement of the temperature of melts in converter vessels



p 16, 1969 w. A. FISCHER 3,466,929

MEASUREMENT OF THE TEMPERATURE OF MELTS IN CONVERTER VESSELS Filed Aug. 19. 1966 Patented Sept. 16, 1969 3 466,929 MEASUREMENT OF THE TENIPERATURE OF MELTS IN CONVERTER VESSELS Wilhelm Anton Fischer, Rafingen, Germany, assignor to Gesellschaft zur Forderung der Eisenhuttenteehnik m.b.H., Dusseldorf, Germany Filed Aug. 19, 1966, Ser. No. 573,512 Claims priority, application Ge4rmany, Aug. 26, 1965,

Int. Cl. GtHk 7/02 US. Cl. 73-343 3 Claims ABSTRACT OF THE DISCLOSURE In the refining of crude iron in converters, it is desirable to be able to supervise the refining process in all stages and thus control it on the basis of the data obtained. One Way which has been proposed for supervising the course of the refining process consists in continuously measuring the temperature of the melt present in the converter vessel. It is not possible to measure temperature by means of a measuring lance inserted into the vessel from above during refining because of the waste gases leaving the converter mouth, the discharge of which cannot be prevented and the charging that takes place at times during refining.

In order to overcome these difliculties, the measuring lance with its thermo-sensitive element, is inserted laterally through the steel shell of the vessel and its refractory lining at a point below the level of the bath formed by the melt. Since the known protective sleeves for the thermo-sensitive elements probably withstand only one charge, it is necessary to provide the element with a new ceramic protective sleeve after each charge. The measuring lance with the element therefore cannot be fitted rigidly and permanently into the refractory lining of the vessel. It must be withdrawn after each charge to replace the element protective sleeve.

In order to make this possible, the lining of the vessel is provided with a steel guide tube for leading the measuring lance into the vessel. It has now been shown that with large converter vessels having refractory wall thickness of about 1 m., it is no longer possible for the guide tube, which extends between the measuring hole and the converter shell, to be fixed rigidly to the converter shell. The expansion of the lining after relining when it is hot blown and during the first charge mostly results in such a severe deformation of the guide tube that it is no longer possible to insert the straight measuring lance.

In accordance with the present invention the vessel of a steel converter has a wall formed by a lining encased in a steel shell and a guide tube extending through the wall for leading a temperature measuring lance through the wall into the vessel, the guide tube passing through an aperture in the shell with a clearance and being sealed to the shell by a flexible seal.

With this arrangement the guide tube is not distorted by expansion of the vessel lining and shell during hot blowing and heating of the first charges.

Preferably the flexible seal is a bellows surrounding the guide tube. In this case a tubular spigot may be rigidly fixed to the outer surface of the lining around the aperture and the bellows is provided at each end with a flange one of which is secured to the spigot and the other of which is secured to an annular flange on the guide rod. When the vessel has reached a substantially uniform temperature after an initial period of use, the bellows flanges can be released from the spigot and guide flange and the bellows removed and replaced by a rigid connection between the guide rod flange and spigot.

One example of a vessel fitted with a lance guide tube in accordance with the invention is shown in the drawing which is a section through part of the converter vessel wall.

The vessel lining is made from tar-dolomite blocks 1 and between these and a steel shell 2 there is a layer of rear ramming mass 3. In the lining there is a perforated block 4 with a boring 5 which is continued through the rear ramming mass 3 to a hole 6 in the shell 2. In the passage 5, 6 there is a guide tube 7 which does not completely penetrate the lining and which at its end projecting beyond the shell 2 has a flange '8, attached by means of screws to a flange 9 of an elastic body 10. This elastic body consists of a flexible bellows 11 which surrounds the guide tube 7 and which has a flange 9, 12 at each end. The flange 12 is attached, by means of screws, to a hollow spigot 13 welded to the shell 2.

While hot blowing the converter after relining, the measuring hole 14 in the perforated block 4 is closed by a solid plug which is only removed for the introduction of a measuring lance with its thermo-sensitive element in the guide tube 7 and the bored passage 5, which provides an extension of the tube. After complete heating of the lining, i.e. after 10 to 20 charges, the elastic body 10 may be removed and replaced by a rigid intermediate piece for subsequent changes. During prolonged shutdowns, of the converter, i.e. on cooling or reheating the vessel lining, the rigid intermediate piece must be replaced again by the elastic body 10. In this it is important that the guide tube 7 should be attached movably or flexibly to the shell while changes occur in length of the lining.

I claim:

1. In a steel converter vessel of the kind having a wall with a lining, a steel shell encasing said lining, a guide tube for leading a temperature measuring lance through said wall into said vessel, and means mounting said guide tube through said lining and shell; the improved guide tube mounting means which comprises wall parts of said lining defining an aperture therethrough whereby said guide tube extends through said aperture with a clearance, and flexible sealing means sealing said guide tube to said steel shell.

2. The invention according to claim 1, wherein said flexible sealing means comprises a bellows surrounding said guide rod.

3. The invention according to claim 2, further comprising a tubular spigot rigidly fixed to the outer surface of said steel shell around said aperture, first and second flanges fixed to the ends of said bellows, a third flange rigidly fixed to said guide rod, means fixing said first flange to said spigot and means fixing said second flange to said third flange.

4 References Cited UNITED STATES PATENTS 5/1963 Fischer et al. 73-343 8/1966 Fischer 73-343 US. Cl. XJR. 

